The present invention relates to the provision of information services to multiple users and, specifically, to a method and apparatus for distributing information to users in the field and for accounting financially for the information distributed to, and selected and received by each user. More particularly, the present invention relates to the provision of a protected archival databank at the user site which permits rapid selection and retrieval of information. The present invention also relates to the provision of information distribution services wherein an alphanumeric character stream containing up-to-date information is serially broadcast to users in the field for selection by each individual user. In addition, the present invention relates to a method and apparatus for providing users with up-to-date information in a "seamless" manner from both an archival databank and periodic updates which are either broadcast or transmitted by storage media. And furthermore, the present invention relates to a method and apparatus for controlling and monitoring the access to information by a plurality of individual information users.
Various information services are available which provide individualized up-to-date information to a user. For example, electronic mail services are available via telephone lines to users of computer terminals. These mail services are based, financially, on either a flat rate subscription or, like dial-up database search services, a user fee which is dependent upon the amount, time spent and type of data provided to the individual user. However, these electronic mail and database search services are costly because the separate information transfers tie up central computer facilities and telephone lines.
Other current information services simply provide a stream of information which is broadcast over AM, FM, TV or satellite channels via cable or electromagnetic radiation. For example, continuous weather broadcasts and sales information provided by retail merchants are available to cable subscribers for a flat fee. Also, stock quotations broadcast on an FM sideband frequency are available to persons having specially adapted receivers. Furthermore, weather and navigation information are provided by U.S. government FM broadcast stations on specially assigned frequencies.
Government weather and navigation information services are supported by public funds. However, the cable TV information services and the stock quotation service must be supported by charges to the user-subscribers. Cable TV service, like the telephone, can be disconnected for non-payment, but the charge is a flat rate for all subscribers. Broadcast information services, such as the stock quotation service, cannot "unplug" a subscriber in this way. The information is therefore available to any user who has a suitably adapted receiver, whether or not they have a subscription to the service.
In considering information distribution services, it is helpful to distinguish between "archival" information, as may be contained in a large databank, and current, up-to-date information, which may be distributed in a serial data stream by telephone line, cable or RF broadcast, or via inexpensive storage media physically sent to the user. The former type of information has classicly been made available from large, on-line, computer databases and distributed by a time sharing system which may include a local area network (LAN), telephone lines, duplex cable, microwave or satellite transmission lines. With the advent of high density storage media such as the compact disk, it has become convenient to furnish significant quantities of archival information on compact disk read only memories (CD-ROMS). CD-ROMS, and other similar high density media can be supplied to users via the U.S. Postal Service, United Parcel Service, Federal Express, or the like.
It is presently the practice of information providers to charge a one-time fee for the information stored on such high density media. The charge for a typical CD-ROM containing, for example, the entire works of Shakespeare must necessarily be prohibitively expensive to many users since the entire value of the information has to be recovered at once. This high initial charge has the effect of limiting the number of potential customers for such information, thereby reducing the user base upon which the information cost can be amortized. This has the effect of maintaining the information charge at an inordinately high level, a "Catch 22" situation which is disadvantageous for both the information provider and the user.
The provision of archival information via high density media which can be read at the user site leaves open the question of periodic updates of current information. The high density media themselves are too expensive to be frequently replaced by media containing the current updates, nor are such updated media necessarily required. It is conceivable to issue "editions" of the archival storage media (e.g. high density CD-ROMS) at longer periodic intervals (e.g. yearly) and to issue incremental updates to this distributed databank to maintain its currency on a frequent basis (e.g., daily, weekly or monthly). The current, update information can be supplied via telephone lines, broadcast channels, or inexpensive low density media such as magnetic tape or floppy disk, as frequently as is required and the information contained on these media may be stored in the user's system (for example on a hard disk memory or optical read/write memory).
In the user search and retrieval from this repeatedly updated databank it is desirable to provide a "seamless" source of information so that the user need not know where the information is actually stored. In such a system, the type and nature of the storage media are said to be "transparent" to the user, who only sees the entire, updated databank as a unit. To the user, therefore, the two types of information described above--namely the archival databank stored locally on a high density media and the current, updates stored locally on lower density media, are preferably indistinguishable.